The inventive concept relates to memory devices, and more particularly to data output buffers and memory devices including the data output buffer.
Careful consideration must be given to the impedance matching between a memory device, or more particularly the input or output buffer of a memory device, and a connected transmission line. Improperly matched impedances will result in undesirable signal reflections on the transmission line. Such signal reflections degrade the integrity of command, address, and/or data signals being communicated on the transmission line.
Noise has always been a design problem related to data transmission systems, but as memory systems run at ever increasing speeds, potential noise sources and conditions have come under renewed scrutiny. Thus, matching between both the termination impedance and drive impedance of a data output buffer and the impedance of a connected transmission line must be address in any emerging memory system design.